Henry measured a line to be 7.8 inches long. If the actual length of the line is 7.4 inches, then what was the percent error of the measurement, to the nearest tenth of a percent?

There is a line with slope 1/a going through the point (a, a²). find the equation of the line perpendicular to this line at this point. (don’t let this problem intimidate you! solve the problem as you would if i’d given you specific values. just use variables instead.)

What is the value of x in the diagram below?

The parabola opens: y=√x-4 (principal square root) up down right left